Horton v. California, 496 U.S. 128 (1990), was a United States Supreme Court case that developed the plain view doctrine under the Fourth Amendment to the United States Constitution. The Supreme Court had already recognized the doctrine in Coolidge v. New Hampshire (1971) and in Arizona v. Hicks (1987), but expanded it in Horton. That expansion included a three-part test, requiring that the police officer finding evidence in plain view be: